Heavy metal pollution and health risk in China

Following rapid social and economic development over the past several decades,pollution by heavy metals has been both serious and widespread in many areas of the world,including China.The situations of heavy metal pollution in China were reviewed,and the health risk and control policy of such pollution were also analyzed and discussed in present paper.

Urea combustion synthesis of LiNi_(0.5)Mn_(1.5)O_4 as a cathode material for lithium ion batteries

LiNi0.5Mn1.5O4 was synthesized by combustion synthesis （UCS） using urea as fuel. X-ray diffraction and scanning electron microscope measurements showed that the spinel structure LiNio.sMnl.504 with the space group Fd3m was formed during urea combustion. Both structure and particle size could be adjusted by the amount of urea and the heat treatment temperature used in the UCS. For the LiNi0.5Mn1.5O4 sample prepared with a urea/Li molar ratio of 0.57 and a heat treatment temperature of 900℃, the particle-size distribution fell in a narrow range of 1-2 Dm. Electrochemical tests indicated that this LiNi0.sMnl.504 sample delivered a discharge capacity of 133.6 mAh/g with a capacity retention rate of 99.6% after 20 cycles at 0.5 C.

Analyses of levels of thyroid hormones and its receptor expression in puerperants and newborns from an e-waste dismantling site

In this study,the serum levels,including thyr-oid hormones free triiodothyronine(FT3),free thyroxine(FT4),thyroid stimulating hormone(TSH)among the sub-jects from the exposed group(n 548)and the control group(n 545)were detected by immuno radiometric assay(IRMA).The expression levels of TRa1,TRb1,TSHR mRNA in placentas and umbilical cords were detected by fluorescent quantitative real-time PCR(FQ-PCR).The correlations between the thyroid hormone levels in maternal serum and umbilical serum,and between the expression levels of its receptors mRNA in placentas and umbilical cords were determined.We found that the FT4 levels of both maternal serum and umbilical cord serum in the exposed group were lower than those in the control(P<0.05).However,the increased TSH levels in the exposed group had statistically significance com-pared to those in the control group(P<0.05).The TRa1 and TRb1 mRNA levels both in placentas and umbilical cords in the exposed group were lower than those in the control group(P<0.05 and 0.01).How-ever,the TSHR mRNA levels in the exposed group were significantly different compared to those in the control group(P<0.01).The serum FT4 and TSH levels of par-turient women were positively correlated with those of the newborns in both groups(P<0.05 and 0.01).The mRNA levels of TRa1,TRb1 and TSHR in the placentas were positively correlated with those in umbilical cords in both groups(P<0.01).The findings suggest that some envir-onmental pollutants existing in the electronic waste(e-waste)dismantling region may affect the health of local parturient women and newborns,representing changes both in serum levels of thyroid hormones and in mRNA expression of its receptors.